N-(1-hydroxyethyl)carboxamide is useful as an intermediate material to synthesize N-(1-alkoxyethyl)carboxamide as being a precursor of N-vinyl carboxylic acid amide.
As a method for producing N-vinylformamide, JP-A-H06-298713 (Patent Document 1) teaches that N-vinylformamide can be produced by thermal decomposition of N-(1-methoxyethyl)formamide produced via N-(1-hydroxyethyl)formamide. However, the publication has no mention on other N-(1-hydroxyethyl)carboxamide or on a method for producing N-vinyl carboxylic acid amide produced via other N-(1-hydroxyethyl)carboxamide.
On the other hand, JP-A-H06-100515 (Patent Document 2) discloses a method for producing N-(α-alkoxyethyl)-carboxamide as being a precursor of N-vinyl carboxylic acid amide from carboxylic amide, alcohol, acetal and the like in the presence of an acid catalyst. This production method is excellent in that the materials are easily available and that N-(α-alkoxyethyl)-carboxamide can be produced in one step without producing N-(1-hydroxyethyl)carboxamide. However, this method requires alcohol and acetal in large excess to carboxylic acid amide; and needs to recover alcohol and acetal from the reaction solution containing N-(α-alkoxyethyl)-carboxamide for recycling, and therefore the method is suitable for mass production but not necessarily suitable for the production in small lots in multipurpose plants.